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In humans, the circulatory system is different before and after birth. The fetal circulation is composed of the placenta, umbilical blood vessels encapsulated by the umbilical cord, heart and systemic blood vessels. A major difference between the fetal circulation and postnatal circulation is that the lungs are not used during the fetal stage ...
Respirations begin when fetal aortic and carotid chemoreceptors are stimulated by the varying concentrations of oxygen and carbon dioxide. During vaginal birth, the newborn's chest is compressed by the birth canal. Upon delivery, negative pressure allows air into the lungs.
Chloride shift (also known as the Hamburger phenomenon or lineas phenomenon, named after Hartog Jakob Hamburger) is a process which occurs in a cardiovascular system and refers to the exchange of bicarbonate (HCO 3 −) and chloride (Cl −) across the membrane of red blood cells (RBCs).
The process of breathing does not fill the alveoli with atmospheric air during each inhalation (about 350 ml per breath), but the inhaled air is carefully diluted and thoroughly mixed with a large volume of gas (about 2.5 liters in adult humans) known as the functional residual capacity which remains in the lungs after each exhalation, and ...
Preterm birth is the birth of an infant at fewer than 37 weeks gestational age. Globally, about 15 million infants were born before 37 weeks of gestation. [147] Premature birth is the leading cause of death in children under five years of age though many that survive experience disabilities including learning defects and visual and hearing ...
From the complete oxidation of one glucose molecule to carbon dioxide and oxidation of all the reduced coenzymes. Although there is a theoretical yield of 38 ATP molecules per glucose during cellular respiration, such conditions are generally not realized because of losses such as the cost of moving pyruvate (from glycolysis), phosphate, and ...
3), and carbon dioxide (CO 2) in order to maintain pH in the blood and duodenum, among other tissues, to support proper metabolic function. [1] Catalyzed by carbonic anhydrase, carbon dioxide (CO 2) reacts with water (H 2 O) to form carbonic acid (H 2 CO 3), which in turn rapidly dissociates to form a bicarbonate ion (HCO −
The pulmonary arteries carry deoxygenated blood to the lungs, where carbon dioxide is released and oxygen is picked up during respiration. [3] Arteries are further divided into very fine capillaries which are extremely thin-walled. [4] The pulmonary veins return oxygenated blood to the left atrium of the heart. [3]